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Changing a specific column name in pandas DataFrame
I was looking for an elegant way to change a specified column name in a DataFrame .
9 Answers
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TypeError: 'NoneType' object is not iterable in Python
What does error TypeError: 'NoneType' object is not iterable mean?
7 Answers
7
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MongoDB inserts float when trying to insert integer
...ed to explicitly specify what type of number we want to use e.g. NumberInt or NumberLong. docs.mongodb.org/manual/core/shell-types
– Yadu
Sep 19 '13 at 16:31
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Difference between size_t and std::size_t
...w). Its defined as unsigned integer type of the result of the sizeof operator.
C Standard says in §17.7/2,
size_t which is the unsigned integer type of the result of the sizeof operator
And C++ Standard says (about cstddef header) in §18.1/3,
The contents are the same as the Standard C ...
How to debug heap corruption errors?
...ngly random occasions, I get a "Windows has triggered a break point..." error with a note that this might be due to a corruption in the heap. These errors won't always crash the application right away, although it is likely to crash short after.
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Would it be beneficial to begin using instancetype instead of id?
Clang adds a keyword instancetype that, as far as I can see, replaces id as a return type in -alloc and init .
4 An...
Why JSF saves the state of UI components on server?
Now, it is no longer necessary to save state while using JSF. A high performance Stateless JSF implementation is available for use. See this blog & this question for relevant details & discussion. Also, there is an open issue to include in JSF specs, an option to provide stateless mode for JSF...
How do I execute a string containing Python code in Python?
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For statements, use exec(string) (Python 2/3) or exec string (Python 2):
>>> mycode = 'print "hello world"'
>>> exec(mycode)
Hello world
When you need the value of an expression, use eval(string):
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'Static readonly' vs. 'const'
...s. We have some classes which contain only constant values. They are used for various things around in our system. So I am wondering if my observation is correct:
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shared_ptr to an array : should it be used?
...llocated array. The shared_ptr template argument in this case must be T[N] or T[]. So you may write
shared_ptr<int[]> sp(new int[10]);
From n4659, [util.smartptr.shared.const]
template<class Y> explicit shared_ptr(Y* p);
Requires: Y shall be a complete type. The expression d...